Canine dilated cardiomyopathy: a retrospective study of signalment, presentation and clinical findings in 369 cases

O bjective : To review the clinical and diagnostic findings and survival of dilated cardiomyopathy from a large population of dogs in England.
M ethods : A retrospective study of the case records of dogs with dilated cardiomyopathy collected between January 1993 and May 2006.
R esults : There were 369 dogs with dilated cardiomyopathy of which all were pure-bred dogs except for four. The most commonly affected breeds were dobermanns and boxers. Over 95 per cent of dogs weighed more than 15 kg and 73 per cent were male. The median duration of signs before referral was three weeks with 65 per cent presenting in stage 3 heart failure. The most common signs were breathlessness (67 per cent) and coughing (64 per cent). The majority of dogs (89 per cent) had an arrhythmia at presentation and 74 per cent of dogs had radiographic signs of pulmonary oedema or pleural effusion. The median survival time was 19 weeks.
C linical S ignificance : Dilated cardiomyopathy occurs primarily in medium to large breed pure-bred dogs, and males are more frequently affected than females. The duration of clinical signs before referral is often short and the survival times are poor. Greater awareness of affected breeds, clinical signs and diagnostic findings may help in early recognition of this disease which often has a short clinical phase.     

Osteoarthritis in cats: a retrospective radiological study

OBJECTIVES: To provide basic information about natural feline osteoarthritis (OA) as part of more extensive studies. METHODS: A retrospective study of cats (greater than one year of age) radiographed for any reason at a first opinion and referral veterinary practice was performed. Cats were classified as either having or not having radiographic OA. Computerised histories were searched for records of potential causes and clinical signs of OA. The genders and ages of the affected cats were compared with a control population using chi-squared tests. RESULTS: Of 491 cats, 292 (59 per cent) had undergone a diagnostic radiograph of at least one synovial joint. Sixty-three of 292 cats (22 per cent) showed evidence of radiographic OA; 21 (33 per cent) of which also had clinically evident OA. A potential cause of OA had been recorded in only seven of 63 cats (11 per cent). The population of cats with radiographic evidence of OA was older than the control population (P<0.001). CLINICAL SIGNIFICANCE: Radiographic OA was found in 22 per cent of the test population. In many cases there was no clinical evidence of OA recorded in the history, suggesting that either there is little correlation between clinical and radiographic OA or that clinical signs of OA in cats may not have been observed or recorded. Idiopathic/primary OA was common.     

Aetiology and outcome in 90 cats presenting with dyspnoea in a referral population

O bjectives : Dyspnoea is an unspecific severe presenting sign, which can be life threatening and requires prompt treatment. Dyspnoeic cats often have significant underlying disease. Underlying aetiologies in cats that presented with dyspnoea were reviewed, and associations with patient signalment and outcome were investigated.
M ethods : The case records of 90 dyspnoeic cats were retrospectively reviewed and separated into different groups depending on aetiology (cardiac, respiratory, neoplastic and trauma). Duration of clinical signs, presentation, hospitalisation length and survival were analysed.
R esults : Cardiac (38 per cent), respiratory (32 per cent) and neoplastic (20 per cent) diseases were common causes of feline dyspnoea. Cats with respiratory causes had longer duration of clinical signs (P<0·001) before presentation. Cats with neoplasia were significantly older (P<0·001). No significant difference in respiratory rates was present between the groups (P = 0·154). High heart rates (P<0·001) and abnormalities on cardiac auscultation were more likely in the cardiac group.
Clinical Significance: Frequent causes of dyspnoea in cats were cardiac disease followed by respiratory causes and neoplastic conditions. Heart rate on presentation and presence of heart murmurs or gallops are useful to identify cardiac causes. Improved proportion surviving was found in the respiratory group (P = 0·027), whereas cats with neoplasia had the worst outcome.     

RADIOGRAPHIC APPEARANCE OF PRESUMED NONCARDIOGENIC PULMONARY EDEMA AND CORRELATION WITH THE UNDERLYING CAUSE IN DOGS AND CATS

Noncardiogenic pulmonary edema is an important cause of respiratory disease in dogs and cats but few reports describe its radiographic appearance. The purpose of this retrospective case series study was to describe radiographic findings in a large cohort of dogs and cats with presumed noncardiogenic pulmonary edema and to test associations among radiographic findings versus cause of edema. Medical records were retrieved for dogs and cats with presumed noncardiogenic edema based on history, radiographic findings, and outcome. Radiographs were reviewed to assess lung pattern and distribution of the edema. Correlation with the cause of noncardiogenic pulmonary edema was evaluated with a Fisher's exact test. A total of 49 dogs and 11 cats were included. Causes for the noncardiogenic edema were airway obstruction (n = 23), direct pulmonary injury (n = 13), severe neurologic stimulation (n = 12), systemic disease (n = 6), near‐drowning (n = 3), anaphylaxis (n = 2) and blood transfusion (n = 1). Mixed, symmetric, peripheral, multifocal, bilateral, and dorsal lung patterns were observed in 44 (73.3%), 46 (76.7%), 55 (91.7%), 46 (76.7%), 46 (76.7%), and 34 (57.6%) of 60 animals, respectively. When the distribution was unilateral, pulmonary infiltration involved mainly the right lung lobes (12 of 14, 85.7%). Increased pulmonary opacity was more often asymmetric, unilateral, and dorsal for postobstructive pulmonary edema compared to other types of noncardiogenic pulmonary edema, but no other significant correlations could be identified. In conclusion, noncardiogenic pulmonary edema may present with a quite variable radiographic appearance in dogs and cats.     

RADIOGRAPHIC AND 2-D ECHOCARDIOGRAPHIC FINDINGS IN EIGHTEEN CATS EXPERIMENTALLY EXPOSED TO D. ZMMZTZS VIA MOSQUITO BITES

Eighteen cats were exposed to Dirofikria immitis infected mosquitoes. Thoracic radiography was performed prior to exposure and at 5, 7, and 9 month intervals following exposure. Immunologic testing for adult heartworm antigen was performed on days 168,195,210,224,237,254 and 271 post infection. Necropsies were performed on all cats. Adult heartworms were found in 61% of the exposed cats. Radiographic findings in heartworm positive cats included bronchointerstitial lung disease, lobar pulmonary arterial enlargement and pulmonary hyperinflation. In most heartworm positive cats, lobar arterial enlargement resolved as the disease progressed while pulmonary hyperinflation progressively became more common. Pulmonary patterns in heartworm positive cats remained abnormal throughoutthe study while abnormal pulmonary patterns resolved in over 50% of the heartworm negative cats. Cardiomegaly was seen in less than 50% of the cats with adult heartworms at necropsy. This study suggests that the radiographic appearance of heartworm disease is variable and radiographic changes are dependent on the time post infection at which cats are evaluated. Echocardiographic examinations were randomly performed on 16 of 18 cats. Heartworms were identified in 7 cats. No false positive identifications were made. Persistent pulmonary disease accompanied by resolving vascular disease in heartworm cats with pulmonary hyperinflation may be difficult to distinguish from cats with feline allergic lung disease. Echocardiograms may be helpful in identifying adult heartworms in cats in which the radiographic signs or immunodiagnostic data are insufficient to provide a diagnosis.     

RADIOGRAPHIC APPEARANCE OF BRONCHOALVEOLAR CARCINOMA IN NINE CATS

Thoracic radiographs of nine cats with confirmed bronchoalveolar carcinoma (BAC) were reviewed retrospectively. Radiographic appearance of BAC was divided into three categories: mixed bronchoalveolar pattern, ill-defined alveolar mass, or mass with cavitation. In addition to these radiographic signs, all nine cats had evidence of some form of bronchial disease. Cavitary lesions were the most common finding (n = 5). In addition, three cats in this category had diffuse bronchointerstitial opacity and one cat had focal peribronchial cuffing. Five cats had either a mixed bronchoalveolar pattern with bronchiectasis (n = 3) or an ill-defined alveolar mass with peribronchial cuffing (n = 2). One cat had both a mixed bronchoalveolar pattern and a cavitary mass. Each of these nine cats had some form of bronchial disease (bronchointerstitial pattern, peribronchial cuffing, or bronchiectasis), which aids in the radiographic diagnosis of bronchoalveolar carcinoma and may represent airway metastasis.     

THE RADIOGRAPHIC APPEARANCE OF PULMONARY HISTOPLASMOSIS IN THE CAT

A retrospective study of 18 cats with pulmonary histoplasmosis was conducted to evaluate radiographic patterns of disease and to determine age, breed, and sex distributions. All cats had active disease confirmed by biopsy/aspiration cytology (lung, bone marrow, peripheral lymph nodes, pleural fluid) or necropsy examination. Cats 3 years of age or less had the highest incidence of disease; females outnumbered males 2 to 1. Radiographically, most cats had an interstitial pattern which appeared as a fine, diffuse or linear pattern, or as a more distinct nodular pattern. An alveolar pattern was an uncommon radiographic finding. Tracheobronchial lymphadenopathy and calcified lymph nodes or pulmonary parenchymal lesions were not identified in these cats.     

Sacral fractures in dogs and cats: a classification scheme and review of 51 cases

classification scheme for sacral fractures was based on a review of sacral fractures in 34 dogs and 17 cats. They were classified into five categories based on their radiographic appearance on standard lateral and ventrodorsal radiographs of the pelvis. Concomitant pelvic injuries were commonly observed: 32 per cent of dogs had a fracture of an ilium and 65 per cent of cats had unior bilateral sacroiliac subluxation. Neurological deficits were common where the fractures traversed the spinal canal or sacral foraminae. Comparison is made between sacral fractures in dogs and cats, and humans.     

A retrospective study of surgically treated cases of septic peritonitis in the cat (2000–2007)

O bjectives : To review aetiology, clinical signs and outcome of cats surgically treated for septic peritonitis (2000-2007).
M ethods : A retrospective study. Inclusion criteria were the identification of intracellular bacteria and degenerate neutrophils and/or a positive culture from abdominal fluid and exploratory coeliotomy. Aetiology, clinical signs, haematological and biochemical parameters, surgical treatment and outcome were recorded and analysed.
R esults : Twenty-six cats fulfilled the inclusion criteria. Abdominal pain was reported in 10 (38 per cent) and vomiting was reported in 11 (42 per cent) of the cats. The most common aetiology was trauma (31 per cent). The principal source of contamination was the gastrointestinal tract. Hyperlactataemia, hypoproteinaemia and hyperglycaemia were reported in 9, 13 and 14 of the 26 cases, respectively. Non-survivors had significantly higher blood lactate concentrations than survivors (P=0·02). Nineteen cats were managed with primary closure, two with closed suction drains and three with open peritoneal drainage. Twelve (46 per cent) cats survived to discharge.
C linical S ignificance : In cats, lethargy, depression and anorexia were more common clinical signs than abdominal pain. Lactate level at the time of diagnosis may be a useful prognostic indicator in cats. The proportion of cats that survived was lower than previously reported and owners should be given a guarded prognosis.     

Management of 60 cases of diaphragmatic rupture

Sixty cases of diaphragmatic rupture in the dog and cat were reviewed. There was a 90 per cent success rate following surgical repair. There were six deaths; two of these resulted from pulmonary collapse and hydrothorax, two cats from pulmonary oedema, one cat with cardiac arrest and one due to hepatic necrosis. In none of the deaths was the presence or absence of chest drains implicated. Apart from cases of gastric dilation, all animals benefited from 12 to 24 hours cage rest and stabilisation before surgery. Simple anaesthetic and surgical guidelines for the management of diaphragmatic rupture are described.     

Radiographic findings in dogs with pulmonary blastomycosis: 125 cases (1989-2006)

OBJECTIVE: To identify radiographic patterns in dogs with pulmonary blastomycosis and radiographic factors associated with outcome. DESIGN: Retrospective case series. ANIMALS: 125 dogs with pulmonary blastomycosis. PROCEDURES: Medical records were reviewed, and for each lung lobe, the primary radiographic pattern and percentage of lobar involvement at the time of initial examination were recorded. RESULTS: 79 dogs survived, 38 died, and 8 were euthanized without treatment. The initial radiographic pattern was variable and not significantly associated with outcome. Mean half-time for radiographic resolution of pulmonary infiltrates was 41.4 days for all patterns except masses, for which mean half-time to resolution was 90.8 days. Transient radiographic worsening was seen in 20 of 87 (23%) dogs but was not associated with a poor prognosis. Pulmonary bullae were seen in 20 (16%) dogs, most often in association with an alveolar pattern. Accuracy of using percentage of right caudal lung lobe involvement ( 20%) to predict outcome was 74.4%; accuracy of using number of affected lobes (< 4 vs >or= 4) to predict outcome was 65.8%. CONCLUSIONS AND CLINICAL RELEVANCE: Results suggested that a nonuniform distribution of pulmonary infiltrates was equally as likely as a diffuse nodular interstitial pattern in dogs with pulmonary blastomycosis. On the basis of half-time for resolution of pulmonary infiltrates, follow-up radiography should be performed no more often than every 4 to 6 weeks in clinically stable patients. Transient radiographic worsening that occurred during the initial weeks of treatment was not associated with a poorer prognosis.     

CARDIAC AND PULMONARY ARTERY MENSURATION IN FELINE HEARTWORM DISEASE

A retrospective study was undertaken to quantify thoracic radiographic changes in cats with heartworm diseases, ( Dirofilaria immitis ). Using a blinded study format, the cardiac silhouette, thoracic cavity and pulmonary arteries were measured from thoracic radiographs of 21 cats with feline heartworm disease and 30 cats without known cardiac or pulmonary vessel pathology. Measured data were normalized to the thoracic cavity or bony structures within the radiographic field of view. The measurements were compared between the two groups of cats using an unpaired, two-tailed Student's t -test, with a p value of < 0.05 being considered significant. Cats with feline heartworm disease had enlargement of the craniocaudal aspect of the cardiac silhouette and normalized cardiac:thoracic ratio (p < 0.05) on the lateral view. Also, there was significant enlargement of the central and peripheral caudal lobar pulmonary arteries and their normalized ratios (p < 0.05) in the heartworm infected cats as visualized on the ventrodorsal projection. Tortuosity of the pulmonary arteries was seen in three of the 21 infected cats. Eleven of the 21 cats with feline heartworm disease had pulmonary parenchymal changes. Based on the present study, central and peripheral pulmonary artery enlargement as viewed on the ventrodorsal radiograph was the single best radiographic indicator of feline heartworm disease.     

Prevalence of radiographic signs of degenerative joint disease in a hospital population of cats

The prevalence of radiographic signs of degenerative joint disease (including appendicular osteoarthritis) among a hospital population of 218 cats was 33.9 per cent (74 cats), and the prevalence of signs of appendicular joint osteoarthritis was 16.5 per cent (36 cats). Half of the cases of appendicular joint osteoarthritis had no apparent radiographic or historical cause, and clinical signs of lameness were recorded in only six of them, all of which had an apparent radiographic cause. The 74 cats with radiographic signs of degenerative joint disease were on average significantly older than the 144 cats in which there were no radiographic signs of the disease.     

Gastrointestinal foreign bodies in dogs and cats: a retrospective study of 208 cases

O bjectives : To establish predilection sites of obstruction and to investigate clinical factors associated with a poor outcome.
M ethods : A retrospective study of 208 consecutive cases over a 48-month period from first-opinion practice.
R esults : Overall, 91 per cent of cases recovered with higher survival rates from discrete foreign bodies (94 per cent in dogs and 100 per cent in cats) as opposed to linear foreign bodies (80 per cent in dogs and 63 per cent in cats). English bull terriers, springer spaniels, Staffordshire bull terriers, Border collies and Jack Russell terriers were over-represented. In dogs, 63 per cent of obstructions occurred in the jejunum but foreign objects were encountered at all points along the gastrointestinal tract. A longer duration of clinical signs, the presence of a linear foreign body and multiple intestinal procedures were associated with significantly increased mortality. Neither the degree of obstruction (partial or complete) nor the location of the foreign body was shown to have a significant influence on survival.
C linical S ignificance : Prompt presentation, diagnosis and surgical intervention improve the outcome of gastrointestinal obstruction by foreign bodies. At surgery, the minimal number of intestinal procedures should be performed to restore the integrity of the alimentary tract.     

Feline extranodal lymphoma: response to chemotherapy and survival in 110 cats

O bjective : To determine response to treatment, survival and prognostic factors for feline extranodal lymphoma in the UK.
M ethods : Records of cats diagnosed with lymphoma of extranodal sites at seven referral centres were reviewed and information on signalment, tumour location, prior treatment and chemotherapy protocol recorded. Factors influencing response to treatment and survival were assessed.
R esults : One hundred and forty-nine cases met inclusion criteria. Sixty-nine cats had nasal lymphoma, 35 renal, 15 central nervous system, 11 laryngeal and 19 miscellaneous locations. Sixty-six cats received cyclophosphamide, vincristine, prednisolone, 25 Wisconsin-Madison doxorubicin-containing multi-agent protocol, 10 prednisolone alone and nine other combinations. The response rate for the 110 treated cats was 85·5 per cent. Of cyclophosphamide, vincristine, prednisolone treated cats 72·7 per cent achieved complete remission, median survival 239 days. Sixty-four per cent of Wisconsin-Madison treated cats achieved complete remission, median survival 563 days. Cats with nasal lymphoma achieving complete remission had the longest survival (749 days) and cats with central nervous system lymphoma the shortest (70 days). If complete remission was achieved, prior treatment with corticosteroids significantly reduced survival time.
C linical S ignificance : Cats with extranodal lymphoma respond to chemotherapy and achieve survival times comparable to other locations. Corticosteroid pretreatment reduced survival time in cats achieving complete remission.     

Clinical evolution and radiographic findings of feline heartworm infection in asymptomatic cats

Clinical manifestations of heartworm disease in cats are variable; most cats seem to tolerate the infection well for extended periods. Heartworm-infected cats may undergo spontaneous self-cure due to the natural death of parasites without any symptomatology, or they may suddenly show dramatic and acute symptoms. Sudden death in apparently healthy cats is not a rare event. Thoracic radiographs are important tool for the diagnosis of cardiopulmonary disease. However, thoracic abnormalities are often absent or transient and highly variable in heartworm-infected cats. Findings, such as enlargement of the peripheral branches of the pulmonary arteries, with a varying degree of pulmonary parenchymal disease and hyperinflation, are the most typical features consistent with infection. A field study was performed for cats referred to the Veterinary Hospital Città di Pavia from January 1998 to December 2001 for routine health examinations and procedures to evaluate the clinical evolution and radiographic findings of feline heartworm infection. Thirty-four asymptomatic cats diagnosed with feline heartworm infection by antibody and antigen tests together with an echocardiogram that allowed worm visualization were included in the follow-up study. Cats were routinely examined every 3 months from the time of heartworm diagnosis until the outcome (self-cure or death). Self-cure was defined as no positive serology for heartworm antigens and no visualization of worms by echocardiography. A final examination for antibodies was carried after 12 months as a final confirmation of self-cure. Twenty-eight cats (82.4%) self-cured; including 21 that showed no clinical signs of infection throughout the study. Six cats died. The most common clinical features observed were acute respiratory symptoms and sudden death. Infection lasted over 3 years in the majority of the cats enrolled in the study. Thoracic radiograph appearance was variable, and the most commonly observed findings were focal and diffuse pulmonary parenchymal abnormalities.     

Evaluation of clinical signs and causes of lower urinary tract disease in European cats

OBJECTIVES: To investigate the clinical signs and causes of lower urinary tract disease (LUTD) in 77 cats. METHODS: Cats diagnosed with LUTD over a two-year period were included in the study. RESULTS: The study population comprised 67 male and 10 female cats. Uroliths occurred in 17 of the 77 cats (22 per cent), urethral plugs in eight cats (10 per cent) and urinary tract infection in six cats (8 per cent). In 44 cats (57 per cent), no specific cause for the disease was found and they were classified as having idiopathic LUTD. In two of the 77 cats (3 per cent) no definitive diagnosis was established. Pain was less common in cats with uroliths and haematuria was more often seen in cats with urinary tract infection. At presentation, urethral obstruction was diagnosed in 45 of the 77 cats (58 per cent). CLINICAL SIGNIFICANCE: The causes of LUTD found in cats in this study are similar to those that have been previously documented, and idiopathic LUTD is the most frequent diagnosis. However, the rate of urethral obstruction, particularly in cats with idiopathic LUTD, was higher than in other reports. The cause of this difference is unknown.     

Hematologic and radiographic changes in cats after inoculation with infective larvae of Dirofilaria immitis.

Hematologic and radiographic findings in 15 domestic cats inoculated with 25, 100, or 200 to 400 infective larvae of Dirofilaria immitis and in 5 uninoculated cats were compared. Eosinophilia and leukocytosis developed 3 to 5 months after inoculation; packed cell volume and hemoglobin values were similar for inoculated cats and controls. Changes detected in radiographs of inoculated cats were: (1) increased visualization of the pulmonary arteries; (2) right-side cardiac enlargement; and (3) diffuse to focal areas of density in the pulmonary parenchyma. At least one of these lesions was visible radiographically by 3 to 7 months after inoculation in all 15 cats. The severity of changes was not directly proportional to the number of infective larvae inoculated, adult worm burden, or age of cat. However, male cats had more severe cardiopulmonary lesions than did females, and cats that had microfilaremia during the course of infection had more severe pulmonary lesions, as determined radiographically. Parenchymal densities decreased in 8 of the 15 inoculated cats 6 to 14 months after inoculation. Cardiac enlargement was detected radiographically in 10 of the inoculated cats. Enlargement of the pulmonary arteries was the most consistent sign of D immitis infection; it developed and persisted in 12 cats found to be infected at necropsy.     

Chiari-like malformation in the Griffon Bruxellois

O bjectives : This study describes Chiari-like malformation and syringomyelia in the Griffon Bruxellois and establishes if skull radiographs are useful for disease prediction.
M ethods : Magnetic resonance imaging from 56 Griffon Bruxellois dogs was assessed for Chiari-like malformation and cerebrospinal fluid pathway abnormalities. Skull radiographs were obtained in 33 dogs. Two rostrocaudal and two ventrodorsal measurements were made, and ratios of one length to another were compared.
R esults : In this selected sample, 60·7 per cent had Chiari-like malformation. Syringomyelia occurred with and without Chiari-like malformation (37·5 and 8·9 per cent study population, respectively). The radiographic study demonstrated that one measurement ratio could be used to predict Chiari-like malformation (sensitivity of 87 per cent and specificity of 78 per cent) and that there were significant interaction factors between sex and syringomyelia for two measurement ratios.
C linical S ignificance : The study suggests that Chiari-like malformation is characterised by a shortening of the basicranium and supra-occipital bone with a compensatory lengthening of the cranial vault, especially the parietal bone. We described a simple radiographic technique, which may be useful as a screening test until a more definite genetic test for Chiari-like malformation is available.     

Clinical efficacy and safety of a once-daily formulation of carbimazole in cats with hyperthyroidism

O bjective : Evaluation of efficacy and safety of a novel controlled-release formulation of carbimazole in feline hyperthyroidism.
M ethods : A multicentre, self-controlled study in 44 client-owned cats with history and clinical signs of hyperthyroidism, and total thyroxine concentration greater than or equal to 50 nmol/l. Treatment was started at 15 mg once daily, response assessed after 10 days, and 3, 5, 8, 26 and 53 weeks and dose adjusted as required.
R esults : The median dose of carbimazole was 10 mg (range 10 to 15 mg) and 15 mg (5 to 25 mg) once daily after 3 and 53 weeks, respectively. Median total thyroxine concentration dropped significantly from 118 nmol/l (50 to 320 nmol/l) at presentation to 33 nmol/l (n=40) after 10 days, 31 nmol/l (n=34) at 3 weeks and 21 nmol/l (n=18) at 53 weeks. Clinical signs improved or resolved in almost all cats within three weeks after starting treatment. Twenty-one adverse reactions possibly (20) or probably (1) related to treatment were reported. During treatment, increased blood urea nitrogen concentration was observed in 25 per cent of the cats, eosinophilia in 20 per cent and lymphopenia in 16 per cent, while liver enzymes tended to improve.
C linical S ignificance : Once daily administration of controlled-release carbimazole tablets was effective and had expected tolerance in hyperthyroid cats during short- and long-term treatment.